"Five myths about why the South seceded"?

Within a post titled Five myths about why the South seceded, one finds the text:

In fact, Confederates opposed states’ rights — that is, the right of Northern states not to support slavery.

AND

The South’s opposition to states’ rights is not surprising. Until the Civil War, Southern presidents and lawmakers had dominated the federal government. The people in power in Washington always oppose states’ rights. Doing so preserves their own.

This argument is bizarre.

Franklin Pierce, the 14th President (1853-1857) was from New Hampshire and declared support for the Confederacy during the Civil War. James Buchanan, the 15th President was from Pennsylvania, and believed secession was illegal AND that going to war to stop it was also illegal, Zachary Taylor, initially from Virginia, was elected as a Whig, and was the last President to hold slaves while in office. As to secession, Taylor noted persons "taken in rebellion against the Union, he would hang ... with less reluctance than he had hanged deserters and spies in Mexico."